全文获取类型
收费全文 | 918篇 |
免费 | 9篇 |
国内免费 | 26篇 |
专业分类
安全科学 | 190篇 |
废物处理 | 17篇 |
环保管理 | 54篇 |
综合类 | 592篇 |
基础理论 | 28篇 |
污染及防治 | 38篇 |
评价与监测 | 23篇 |
社会与环境 | 6篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 9篇 |
2022年 | 4篇 |
2021年 | 33篇 |
2020年 | 43篇 |
2019年 | 13篇 |
2018年 | 1篇 |
2017年 | 15篇 |
2016年 | 22篇 |
2015年 | 39篇 |
2014年 | 52篇 |
2013年 | 37篇 |
2012年 | 19篇 |
2011年 | 57篇 |
2010年 | 21篇 |
2009年 | 50篇 |
2008年 | 32篇 |
2007年 | 42篇 |
2006年 | 39篇 |
2005年 | 59篇 |
2004年 | 38篇 |
2003年 | 49篇 |
2002年 | 47篇 |
2001年 | 40篇 |
2000年 | 42篇 |
1999年 | 32篇 |
1998年 | 25篇 |
1997年 | 29篇 |
1996年 | 14篇 |
1995年 | 15篇 |
1994年 | 14篇 |
1993年 | 7篇 |
1992年 | 7篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1986年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有953条查询结果,搜索用时 78 毫秒
91.
Binbin Sheng Depeng Wang Xianrong Liu Guangxing Yang Wu Zeng Yiqing Yang Fangang Meng 《Frontiers of Environmental Science & Engineering》2020,14(6):93
92.
从垃圾渗滤液的末端处理技术,即预处理、生物处理、后续处理三个方面分析了垃圾渗滤液的单独处理技术,并对渗滤液的回灌技术进行了论述。 相似文献
93.
94.
本项目以哈尔滨啤酒(沈阳)有限公司啤酒厂为设计对象,其啤酒废水处理规模为1500m3/d,进水CODCr2000~2800mg/L。采用预处理-预酸化-IC反应器-活性污泥法-过滤为主体工艺,出水达到《辽宁省污水与废气排放标准》(DB21-60-89中一级标准)。为啤酒行业废水综合治理提供了较好的工艺途径。 相似文献
95.
煤与瓦斯突出影响因素评价分析的模糊层次分析方法 总被引:6,自引:3,他引:3
在综合分析煤与瓦斯突出的影响因素的基础上,采用模糊层次分析法(FAHP)建立了煤与瓦斯突出模糊层次分析模型并进行了实例分析,确定了煤与瓦斯突出各影响因素的权重系数。评价结果表明:地应力、地质构造、瓦斯压力等是影响煤与瓦斯突出的主要因素。为制定相应的煤与瓦斯突出防治措施,提供了科学的理论依据和切合实际情况的评价方法。 相似文献
96.
If no data are available for a specific radionuclide its analogue could be used in radioecological models. They might be used not only in the frame of screening modelling. Relevant processes and features have to be known, such as time scales of these processes, physical, chemical and biological properties of the environment and relevant media. An analogue could only be proven to be valid by comparing its behaviour in the conditions of interest, while confidence in the validity of an analogue will increase as the quality of the justification increases, there will always be some residual uncertainty. Several main types of analogy can be used when measured or recommended values are not available: the same parameter obtained for another isotope of the same element; the same parameter obtained for another element; a different parameter obtained for the same element. There are several cases, when analogues might be applied as indicators of the determining processes in the radioecological studies. 相似文献
97.
Hctor Medina Josep Arnaldos Joaquim Casal 《Journal of Loss Prevention in the Process Industries》2009,22(5):566-573
Hazard identification and risk assessment are key aspects in process plant design. They are often applied in the final stages of the process at whatever the cost, unless financial constraints are imposed. However, a much better solution would be to introduce risk analysis earlier by including it in earlier stages of the design process, such as when the cost of a plant and the cost of any accidents that may occur are estimated. In this paper, an optimization methodology is proposed, in which both cost and risk (with a deterministic approach) are taken into account, to improve on the current situation. If a decision variable is chosen, an objective function will be established that makes it possible to analyze variations in overall costs, including the cost of the investment and the cost of accidents. This leads to an optimum situation in which costs are kept to a minimum. Of course, this optimization is subject to constraints, the greatest of which is the fact that risk must not exceed tolerated threshold levels. The procedure is explained and two examples, one involving a toxic release and the other a BLEVE/fireball, are used to illustrate it. 相似文献
98.
A systematic approach to optimizing water network has traditionally been utilized to exam and plan water conservation in industrial processes. In the present case study, water-pinch technology was used to analyze and optimize the water network of a steel plant near China's Zhangjiakou city. A system design was developed and a limiting constraint (Cl(-) concentration) was identified based on investigations of water quality then the minimum freshwater and wastewater targets were determined without considering water losses. The analysis was then extended by calculating the additional input of freshwater required to balance the actual water losses. A nearest-neighbor algorithm (NNA) was used to distribute the freshwater and recycled water among each of the plant's operations. The results showed that with some reconstruction of the water network, the flow rates of freshwater and wastewater could be decreased by 57.5% and 81.9%, respectively. 相似文献
99.
影响超高压输电线路可听噪声的因素众多,对影响可听噪声的因素进行合理分析确定其对可听噪声影响的权重是进行可听噪声预测和合理有效降低可听噪声的前提。对影响可听噪声的因素进行分析并运用层次分析法(AnalyticHierarchyProcess,AHP)对影响可听噪声的主要因素进行加权分析,以定量的形式确定影响因素的相对重要度。结果表明,应用层次分析法确定的可听噪声影响因素权重符合实际,准确性较高,为可听噪声选择主要影响因素用于预测及有效降低可听噪声提供参考依据。 相似文献
100.